ISSN:
1573-5117
Schlagwort(e):
Mesocosms
;
nutrients
;
bacteria
;
phytoplankton
;
zooplankton
;
fish larvae
;
microbial food web
;
E Mediterranean
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
Notizen:
Abstract A mesocosm experiment was conducted in order to studythe structure of the planktonic food web. The dynamicsof pico-, nano- and microplankton populations werefollowed during 40 days in four large (40 m3)enclosures. In three tanks a gradient of addednutrients (nitrogen and phosphorus) was applied, whilea fourth tank was used as a control. On day 14, thetop predator (sea bream Sparus aurata larvae)was introduced into the tanks and part of the watercolumn in each tank was isolated in a plastic bagwithout fish larvae, to act as a control forpredation. Physical parameters, chlorophyll aand nutrient concentrations, as well as planktonconcentrations were monitored. A diatom bloom wasobserved in all four tanks, in the first phase endingwith silicate depletion. Flagellate and dinoflagellateabundance subsequently increased, these organismsbeing limited by zooplankton grazing. The zooplanktonpopulations were controlled by both resources (mostlyflagellates) and predation (by fish larvae) asindicated by the results of the control experiments.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1023/A:1003121704913
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